Comparative transcriptome and metabolome analyses identified the mode of sucrose degradation as a metabolic marker for early vegetative propagation in bulbs of Lycoris

Abstract

Vegetative propagation (VP) is an important practice for production in many horticultural plants. Sugar supply constitutes the basis of VP in bulb flowers, but the underlying molecular basis remains elusive. By performing a combined sequencing technologies coupled with ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry approach for metabolic analyses, we compared two Lycoris species with contrasting regeneration rates: high-regeneration Lycoris sprengeri and low-regeneration Lycoris aurea. A comprehensive multi-omics analyses identified both expected processes involving carbohydrate metabolism and transcription factor networks, as well as the metabolic characteristics for each developmental stage. A higher abundance of the differentially expressed genes including those encoding ethylene responsive factors was detected at bulblet initiation stage compared to the late stage of bulblet development. High hexose-tosucrose ratio correlated to bulblet formation across all the species examined, indicating its role in the VP process in Lycoris bulb. Importantly, a clear difference between cell wall invertase (CWIN)-catalyzed sucrose unloading in high-regeneration species and the sucrose synthase-catalyzed pathway in low-regeneration species was observed at the bulblet initiation stage, which was supported by findings from carboxyfluorescein tracing and quantitative real-time PCR analyses. Collectively, the findings indicate a sugar-mediated model of the regulation of VP in which high CWIN expression or activity may promote bulblet initiation via enhancing apoplasmic unloading of sucrose or sugar signals, whereas the subsequent high ratio of hexose-to-sucrose likely supports cell division characterized in the next phase of bulblet formation.

Auxin regulates bulbil initiation by mediating sucrose metabolism in Lilium lancifolium

“…It has been reported that SUS and IVR mediate sucrose metabolism in plants [ 24 ]. According to the reverse transcription–quantitative polymerase chain reaction (RT–qPCR), NPA treatment significantly increased the expression of genes involved in sucrose metabolism in leaf axils, including LlSusy1 , LlSusy2 , LlCWIN2 , and SOLUBLE ACID INVERTASE ( LlSAI ), which was consistent with the FPKM (fragments per kilobase of exon model per million mapped fragments) value in the transcriptome.…”

“…Increased expression of genes involved in sucrose metabolism, such as those encoding SUS and IVR pathways, can promote early organogenesis. In the species Gladiolus hybrida and Lycoris , specific genes like GhSUS2 and LsSUS4 facilitate the process of sucrose downloading, leading to an increase in the number of corms and bulblets [ 23 , 24 ]. Furthermore, a class of IVR called cell wall invertase can regulate sucrose transport by the apoplast pathway and promote cell division.…”

Combined analysis of the transcriptome and metabolome provides insights into the fleshy stem expansion mechanism in stem lettuce

“…As an energy substance for plant growth and development, sugar involve in plant growth and development as a signaling substance ( Peng et al., 2018 ). Sucrose played a key role in integrating developmental stages and environmental cues to regulate plant yield ( Fernie et al., 2020 ; Liao et al., 2020 ; Wu et al., 2021 ; Ren et al., 2022 ). In this study, the sucrose content was highest in the early stage of stem expansion in lettuce, indicating that it stored a large amount of energy in the early stage for the later stem expansion.…”

Integrated proteomic, transcriptomic, and metabolomic profiling reveals that the gibberellin–abscisic acid hub runs flower development in the Chinese orchid Cymbidium sinense

“…The floral metabolome was detected using ultra-high-performance liquid chromatography (UHLC) as previously described [ 63 ].…”